131401991 has 8 divisors (see below), whose sum is σ = 152636064. Its totient is φ = 110783520.

The previous prime is 131401973. The next prime is 131402009. The reversal of 131401991 is 199104131.

It is an interprime number because it is at equal distance from previous prime (131401973) and next prime (131402009).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 131401991 - 2¹⁰ = 131400967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131404991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153440 + ... + 154293.

It is an arithmetic number, because the mean of its divisors is an integer number (19079508).

Almost surely, 2^131401991 is an apocalyptic number.

131401991 is a deficient number, since it is larger than the sum of its proper divisors (21234073).

131401991 is an equidigital number, since it uses as much as digits as its factorization.

131401991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307801.

The product of its (nonzero) digits is 972, while the sum is 29.

The square root of 131401991 is about 11463.0707491492. The cubic root of 131401991 is about 508.3942717473.

The spelling of 131401991 in words is "one hundred thirty-one million, four hundred one thousand, nine hundred ninety-one".